


Eat Your Heart Out, Wolfgang Pauli

by ishie



Category: Big Bang Theory
Genre: Bodyswap, Crack, F/M
Language: English
Status: Completed
Published: 2010-12-22
Updated: 2010-12-22
Packaged: 2017-10-17 08:18:01
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,732
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/174786
Author URL: https://archiveofourown.org/users/ishie/pseuds/ishie
Summary: <blockquote class="userstuff">
              <p>Of course, the answer is standing right in front of him. In the mirror. There's a bed and wall reflected behind him, a riot of color that clashes with tanned skin and rumpled pajamas and a cloud of blonde, blonde hair.</p><p><i>He's</i> Penny.</p>
            </blockquote>





	Eat Your Heart Out, Wolfgang Pauli

**Author's Note:**

  * For [d_sieya](https://archiveofourown.org/users/d_sieya/gifts).



> A/N: Huge, huge thanks to htbthomas and inkdot for the beta & encouragement, and to my own horrific first time taking a drinks order many, many jobs ago. No Austrian physicists were harmed in the making of this fic. For your own safety, have brain bleach ready before viewing the [related minimix cover at the end of this entry](http://community.livejournal.com/ishieland/31393.html). Guests with severe crack allergies should seek alternatives immediately.

Every morning Sheldon Cooper experiences a brief instant of panic, of unremitting, jaw-clenching, bowel-loosening terror. His eyes open but no visual stimuli registers. His hearing is functional but he can't make sense of the noise ringing through his head. There is something under his hand, something warm and soft, then colder and soft, then cold and hard and vibrating. His fingers twitch. The sudden cessation of noise is a shock, jump-starting his synapses and setting him on the path back to reality.

It takes milliseconds, at most. But in that brief span between unconsciousness and awareness, it feels as though he has been unceremoniously flung into alternate dimensions: Flatland, the precursor to the Terran Empire, a world in which turtles snap at his heels as he floats through an underwater city. It's whimsy, nothing more. A random firing of neurons as the familiar becomes familiar again after a full night's sleep.

He's always grateful to pull his hand away from the alarm, safe and secure once more in his own body. His own mind. His bed, his pajamas, his skin.

Until one day, it all goes wrong. Horribly wrong. This is wrongness on levels he's never previously encountered. They might even be unmeasurable by any human or superhuman standards.

This has to be Penny's fault.

 

 

"Sheldon," a voice roars. It's somewhere between tenor and baritone, a twang sliding each monophthong almost to the point of dipthong....

Oh. It's his voice. But it's not coming from his throat. He knows it's not coming from his throat because for the past few seconds, ever since he launched himself out of the bed (and in which universe is he that a person in their right mind would clutter their bed with so many pillows), he's been standing in front of a mirror. Slack-jawed. If there were a voice coming from him, it wouldn't be using words, just formless syllables. Guttural nonsense.

Well, technically, the voice that's using words is coming from his throat. It's just that it's not the same throat as the one he's controlling at the moment.

"Penny?" he tries. It comes out timid and hushed. He can't help but catalog the feel of this throat he's using, the way it constricts slightly on the second syllable. The voice that comes out of it is closer to a tenor than he thinks should be normal, so he clears the throat and tries again. "Penny, is that you? Where are you?"

Of course, the answer is standing right in front of him. In the mirror. There's a bed and wall reflected behind him, a riot of color that clashes with tanned skin and rumpled pajamas and a cloud of blonde, blonde hair.

He's Penny.

 

 

Slack-jawed doesn't really do his expression justice.

It's more along the lines of dumbstruck, in every sense of the word. With a side of horrified. To the nth degree.

If his mother were there, she would doubtless tell him he looks like his daddy did every single time he fired up the lawnmower after it chopped off his little toe. Except also — improbably, impossibly — like a girl. In a disturbingly brief pair of sleep shorts.

That's what she would say once she stopped trying to wrap him in a robe and praying to Jesus to whip the devil right out of her boy, that is.

 

 

Navigating through the piles of laundry, discarded magazines, shoeboxes, and other assorted detritus is astonishingly easy. Even as most of his cognitive functions turn even farther toward madness and sheer, gibbering terror, he wonders if it's due to muscle memory.

"Sheldon," his voice bellows again, this time accompanied by blows to the apartment door that sound as if they'll knock it right off its hinges. "Open this door before I kick it down."

Can his body even do that? He looks after himself, of course, maintaining optimal levels of caloric intake and keeping his daily activities within an acceptable ratio to the nutrients he consumes. But kicking down a door? That doesn't seem likely. While he is certainly the most athletically inclined of his small circle of friends (discounting Penny, for the moment; the continuing threats from the hallway don't bode well for their continued association), he's never considered whether he has the capacity for violent, destructive actions.

Beyond the occasional daydream in which he discovers that his replica Green Lantern ring has been switched with the real thing, of course.

He stumbles over a pair of shapeless, dingy boots in front of the TV, but the proportions of this body are so alien to his own that he overcompensates for the forward motion and falls elbows-first onto the floor.

Everything else is a jumble, even afterward when he's regained consciousness and tries to sort it out: cursing that would make his pawpaw blush; the burning sensation of skin chafed by cheap artificial fibers; darkness rising from the rug; an outraged bellow; his vision blotted out by a field of plaid; someone calling his name; the room quadruplicating itself; a groan that sounds more like a whimper; the sound of the door flying open.

Something slamming into his temple, that he's very clear about. That's the very last piece of the jumble, but it fits almost exactly where it should.

 

 

"This is unacceptable," he hears himself say in the darkness.

Oh, thank goodness, oh Lord, thank you, Lord, oh, bless you, he thinks, with a huge surge of relief that carries him right back to the days when he still reveled in the glory of God and all His creation. He's scolding Leonard in his sleep again; that's nothing new. A nightmare. That's all this is, a simple nightmare. He'll wake up any moment and—

But in the very next second, the relief flees as quickly as belief once did as he hears himself continue.

"If you touched one damn thing you shouldn't, I am going to kick your ass from here to Reseda."

He wonders if his voice has always been this ... screechy.

 

 

The pain comes rushing in first, a tidal wave sluicing out the last remnants of oblivion, blotting out whatever other senses are slowly coming back online until — ka-pow — there they are. All of them. Slamming into him full blast, like jet wash.

Though he's not aware of it, Sheldon must make a noise of some sort because the field of plaid shifts and hands grab at his shoulders, pushing him onto his back. The air is cool on his stomach. More hands — the same hands? — brush against the smooth skin until it's covered with the fabric of the tank top he's wearing.

He bats the hands away and tries to sit up.

But halfway through the motion, he freezes as he suddenly becomes aware of several things, simultaneously:

1) His face looks very peculiar from this angle;

2) He's due for another haircut, at least two days ahead of schedule;

3) Good Lord, are breasts supposed to move like this?

 

 

This isn't a dream. He's at least 94% sure of it now. To begin with, despite all his claims of superior intellect and brain function, there is simply no way that he could have known that Penny keeps an icepack in her freezer, under a carton of Zero candy bars. The farthest he's ever gone into the depths of her kitchen is to recoil in horror at the smells that waft out of her refrigerator, even when the door is closed and sealed.

Nor could he have known that her first aid supplies are stashed in her closet, under a program for the 2006 Rose Bowl Parade and a half-knitted scarf. He's usually the one dispensing band-aids and antibacterial ointment, not the other way around.

And no experience in his entire life — both real and virtual — could have given him the capacity for imagining what it would feel like to actually be her.

He's perched on the seat of Penny's toilet, looking down at Penny's hands, folded neatly in Penny's lap. Her elbows sting where they've been scraped raw by the cheap rug. Her nails are buffed short, with a chipped slick of red polish covering all but the pinkies. Beyond that, Penny's knees, more red, irritated skin painted with iodine. Penny's feet: tanned, narrow, toes ringed with silver and beaded gold. He wiggles his toes, watches hers do exactly what his brain is telling them to do.

He feels faint. Fainter. Oh Lord, is being in her body starting to affect his intellect and reasoning?

"Oh, my God," she mutters as his breath starts to get choppy. It's far from the first time that morning, and he's only been awake (this time) for ten minutes. She repositions the icepack against the lump that the door raised. "Would you just chill out for two seconds?"

There is so much wrong with hearing those words, that tone, directed at him in his own voice that it starts to make him queasy.

"Excuse me," he snipes back. "I didn't realize my rate of respiration was so offensive to you."

His own bare feet come into view, stepping to either side of Penny's leg. His hand grips him under the chin and tilts her head up so that their eyes meet.

It's difficult for him to decipher her expressions. With four years of experience with every conceivable eyebrow raise, he still gets it wrong almost as often as he gets it right.

But it's impossible now to decipher Penny's expression when it involves his own features.

 

 

Once her body is patched up, Penny grabs him by the elbow and drags him out into her living room. She crosses his arms and purses his mouth.

The resemblance Sheldon bears to his mother when Penny's in control of his face is disturbing.

"Look, I don't really care right now how the hell you did this. Just, fix it. Now."

"What I did?"

"Yeah, this is really something I could do." She snorts and raises a hand to pull on a lock of hair, a common sign of agitation when she's in her own body. But his hair is too short and the hand flutters at his temple before dropping back to her side. "Just, go fix whatever crazy-ass thing you built that did this so I can get to work. We never have to talk about it again."

He takes a deep breath. "I didn't do this."

She narrows his eyes and he takes an involuntary step backward.

"I don't know how this happened?" he offers.

"What do you mean, you don't know how this happened? People don't just wake up in the wrong body, Sheldon."

"Apparently they do."

She drops onto her couch, pinching at the bridge of his nose. A tension headache? Since he usually only gets them when he's dealing with his family and Leonard, he'd assumed they were psychosomatic manifestations of his frustration. That Penny appears to be suffering from one... He'll need to make an appointment for another neurological workup as soon as their current situation is resolved.

Sheldon sits gingerly on the coffee table, after arranging all the separate piles of magazines into one neat stack.

"What are we going to do?" Penny asks. Whatever expression she thinks she's making, it makes his face look like he's suffering from a severe case of indigestion. She plucks at the pajama pants he'd put on the night before. "We can't stay like this."

"No, this is clearly an untenable situation."

He would go on, how the reaction her physical form gets in public is more than he thinks he's comfortable handling. That the thought of Penny having to take care of his body's more personal functions makes clammy sweat bead under her arms.

But she's starting to fidget, his long legs dancing with her customary impatience.

"Was Leonard awake when you came over?"

She squishes up his face, his eyes looking up as she tries to remember. "No, I don't think so."

"Good. If he follows his usual pattern, he won't be up for another half an hour. Go back to my apartment and lock yourself in my bedroom. Where's your laptop?"

Penny folds his body in half and sticks his arm under the couch. Sheldon tries not to scream when she pulls it back, a dust bunny clinging to the sleeve of his pajamas and her laptop in hand.

Faintly, he says, "I'll send a sick day notification to my email distribution list. That will keep everyone at bay for at least two days."

It's a herculean effort for Sheldon to tear her eyes away from the clump of dust and god only knows what else that's swaying in an imperceptible breeze, millimeters away from his skin. Penny gets tired of waiting for him to take the laptop and drops it on the couch with an exasperated noise. The dust transfers from the sleeve to the cushion, a brownish smear of dirt against the bright fabric.

He closes her eyes in relief. There's a whisper of fabric on fabric as Penny stands, then the sound of soft footfalls as she heads for the door to the hallway.

"Should I, uh. Do you want me to, um, I know you're big on hygiene and everything—"

If he looks at her, will the face she's wearing be red with embarrassment or green with nausea? Sheldon decides he doesn't want to know and looks out the window instead. He's starting to feel dizzy again, contemplating all the thousands upon thousands of ways their situation is straight out of one of his worst nightmares.

"Let's just agree," he says to the sky outside the window, "to pretend this is a dream, unless we're talking about solutions."

It solves nothing, least of all the bladder issues he knows will become pressing sooner or later. It doesn't even make any sense to dance around the question; they'll each have to confront it sooner or later, and live with it afterward, unless he can also invent a stable memory-wiping device.

But Penny makes a strangled noise of agreement and pulls the door closed behind her before he can change his mind.

 

 

 

Moments after Sheldon hits send on his email and logs back out of the Caltech VPN, he hears Leonard stumbling out of the apartment, shouting something about a lab emergency. Sheldon's voice follows after him, a high, nasal drone demanding soup, softer tissues, and another humidifier.

Surely that's not what he sounds like when he's ill?

He looks out Penny's window and sees Leonard run right past his parked car on the street. His messenger bag isn't properly sealed and papers float in his wake like molting feathers.

"Good Lord," Sheldon mutters. Perhaps it's time to start interviewing for a new roommate, after all.

Penny lets herself back into the apartment, giggling and clutching his stomach. "Did you see his face?" she gasps.

It's another minute or so before she has herself under control again. The whole time, Sheldon stands awkwardly by the windows. Why is she back here? His laptop, all of his theoretical texts, his whiteboards — everything he'll need to try to reverse their situation, or pinpoint its cause, is in his apartment.

"Sorry," she says, sounding the exact opposite. She straightens his pajama top and flops down onto the couch again. He winces at the thought of the damage she's doing to his spine.

"So, you figure out what's going on yet?"

Sheldon snorts. It's been less than an hour since he woke up in the wrong apartment, the wrong bed, and the wrong body. There hasn't been enough time to find her spare toothbrushes, if she even has any, let alone sort out how on Earth they've gotten into this mess.

Now that expression he recognizes from the pep talks he has occasionally had to give himself, when nerves and general human weakness got the better of him. That's determination.

"Well, while you're running my shift at work, what can I do?"

What can she do? Unless her hair spray and scented lotions have started doing double duty as hex reversals or quantum recombinators straight out of the novels on his shelf, there isn't anything she can do but sit there and not damage him any further.

Wait.

He drops into the nearest chair when her knees suddenly give out on him. "Work? You want me to go out in public like this?"

 

 

Not only does she want him to go out in public, she has a thousand and one demands about how he has to look, act, smile, talk, and walk while he's out there. None of his arguments have any effect.

She even expects him to drive.

"No one's going to believe that you're taking me to and from work, Sheldon," she explains, not unreasonably. "You'll be fine."

"But. But what about...." he can't figure out how to finish the question, much the same way she did earlier. He waves a hand in the vicinity of her skimpy pajamas.

If he had more time, and less traumatic circumstances, Sheldon thinks he'd like to catalog all the different ways she creates expressions on his face that he's never seen before.

"I showered before I went to bed," she says, "so just get some deodorant and get dressed."

It's a horrifying answer, but slightly less horrifying than some of the other options before him. She follows him into her bedroom and pulls a clean — thank God — uniform and a bra out of her dresser.

"Just, don't look," she says without looking at him. "And don't touch anything. I'd do it for you but, I mean... What if you somehow remember once we're switched back? I don't...."

So she's said before. As she trails off, he nods, hoping she'll see it out of the corner of his eye. By the tightness in his throat, he's pretty sure words aren't an option.

Once the door closes, Sheldon realizes that not looking might not be an option either. It was difficult enough helping her get dressed when she dislocated her shoulder; then he was just an extra set of hands following her instructions.

The bra is a flimsy-looking cotton item with hooks and eyes that look too small to be functional. He fastens it and tries to pull it on over her head, but the elastic only gives a fraction of an inch and he can't get it farther than her elbows. Plus, he forgot that he was still wearing the tank top she slept in, and he has no idea how that would come off even if by some miracle he managed to get the bra to cooperate.

"This is asinine," he declares to her reflection in the mirror. It's tempting to put the bra back and get dressed without it, but even the smallest movement sets her breasts to swaying. It's distracting enough while he's walking around in her apartment, he can't imagine how he'll be able to wait tables.

A few minutes of experimentation leads him to wrapping the bra around her midsection, fumbling the hooks closed in front, then twisting the whole contraption around to the right position.

Sheldon takes a deep breath and squeezes her eyes closed as he pulls the tank top free and up over her head. The jiggling and swaying starts again, goosebumps popping up on her back and arms, nipples tightening against the cold and friction and movement as he struggles to push and pull the bra into place.

The edge of one soft cup cuts into the flesh of her right breast and, without thinking, Sheldon reaches in to reposition it. The pebbled skin against her fingers; the silky warm weight of it in her palm; the slightly scratchy feel of the cotton against the back of her hand....

Her pulse starts to pound in her ears and Sheldon's suddenly aware of the thrum of blood quickening in her— Oh.

Her eyes fly open as Sheldon pulls the hand away from her skin. In the mirror, all he can see is tanned skin and soft flesh and there's a sudden tugging sensation that feels like it's connected to everything between her sternum and her thighs.

It's not an entirely unfamiliar sensation, just one he's not used to feeling untethered from his own anatomy. And certainly not one he's ever had while contemplating his own body.

"Well, that's disconcerting."

 

 

He lasts all of two hours at the Cheesecake Factory.

He'd bit his (Penny's) tongue while she walked around her apartment in his bare feet. Compared to what else she could do, the admittedly low risk of athlete's foot seemed the lesser of many, possibly crippling and permanent, evils.

Keeping his peace as he witnesses line cooks and servers alike openly flaunting health code regulations is almost more than he can bear. But bear it he does, because she still holds his body hostage, and because the possibility of a jobless, homeless Penny is somehow too terrible to contemplate.

The few hours he worked as a busboy means he's already familiar with the layout of the kitchen. After four years of carefully testing every four- and six-top and booth in the restaurant, he knows the layout of the dining room and the breakdown of the serving sections like the back, palm, and heel of his hand.

He fumbles his way through taking the first table's drink orders — how was he supposed to know no one takes their beer in a glass with ice! In his admittedly limited experience, people drink it out of plastic funnels and other people's mouths and even, on certain traumatic but mandatory family hunting trips, from boiled deer skulls. How on Earth is an ice cube an offensive addition? — and by the time the lunch rush is starting, he's confident that taking over this aspect of Penny's life will be as easy as solving quadratic equations.

Everything is perfect, until Bernadette corners him by their shared drinks station.

 

 

He doesn't know what it signifies when one is walking like a cross between John Wayne and Bigfoot, but he tries again to modify his gait to better suit Penny's legs. It's when Bernadette follows that cryptic statement with an exaggerated wink and a request for "all the dirty details" that he realizes she might not have been remarking on his walk.

He does know that she sometimes reminds him of Howard more than he's comfortable with.

It isn't until the third time that she corners him, this time with a grin that seems to swallow the rest of her face and an excruciating recitation of her own recent carnal activities, that he recognizes that he has to get out of there. Now. Twenty minutes ago, even, were he able to bend the space-time continuum just this once.

Sheldon blames the tight ties of Penny's apron and the coffeepot warming a few inches from his elbow for the sudden onset of labored breathing and perspiration.

 

 

When he let himself back in to Penny's apartment — they'd agreed it was the safer of the two options, even with the threat of debilitating illness hanging over his own — it only took a single phrase for her to stop yelling about running out in the middle of her shift.

"Howard and Bernadette rented a honeymoon suite in Vegas last weekend."

She recoiled so hard, he'll be lucky if there isn't permanent damage to his anterior longitudinal ligament.

While he was gone, Penny had taken the list he'd made of materials he needed and brought it all over from his apartment. Sheldon sets up his laptop on her dinner table and stares at the screen. He doesn't have any idea where to start. The last thing he remembers is getting ready for bed the night before: the same routine, the same everything. He hadn't been on campus. She folds herself into an uncomfortable position on the couch and turns on the TV, only muting the mindless makeover show when he clears her throat for the dozenth time.

"Do you want me to help?" she asks.

"Do you even know what I'm looking for?"

"...No."

"Then no."

"Do you even know what you're looking for?"

He doesn't dignify that with a response, just kept paging through a book on theoretical energy transference principles.

 

 

When her show ends, she turns to an old black and white monster movie and twists around to drape his arms over the back of the couch.

"Are you keeping, like, weird Egyptian stuff in your apartment? Like, mummy parts?"

"No."

She looks disappointed. "Wish on any stars?"

"That's a load of superstitious nonsense."

"Sheldon, we're wearing each other's skin right now."

He concedes the point.

 

 

"Did you kill a gypsy?"

"I'm not speaking to you."

 

 

 

At some point, she pushes herself off the couch, makes a crack about the popping noises his spine makes when she straightens to his full height, and throws a frozen pizza in the microwave. The sun is bright outside, and the bus squeals to a stop at the corner every seventeen to twenty-one minutes.

Sheldon keeps clicking, finding himself straying farther from reputable websites with every passing moment. Penny's hair is tangled, nearly standing on end, from all the time he's spent worrying it as he searches. Her eyes burn, dry and irritated, and there's a tickle in her throat that leads him to believe that her allergies might rival his own.

He looks up from the screen to find her looming over his shoulder.

"What are you looking at?"

"Absolutely nothing."

"So, basically we're exactly where we were when we woke up this morning. Ugh."

Sheldon holds up a finger, ready to shift into a lecture about the impossibility of maintaining a fixed position in space, but Penny shoves a plate of steaming pizza at him instead.

 

 

Penny slumps down in her seat, letting his head roll against the back of the couch. "All right, all right. So two things can't exist in the same place. Duh. What does that have to do with how my head wound up in your body?"

Sheldon's sigh is deep enough to stir the napkins on the coffee table. He isn't sure, entirely, what the connection is either, but if he can get her to understand where his speculations are starting, maybe they have a chance of fixing it.

He sits up straighter and rewinds to the beginning of the lesson. "In 1925, Wolfgang Pauli postulated that particles with a half-integer spin must have distinct quantum numbers—"

"I can't take this anymore," she groans. "Hold still, Einstein, I saw this in a movie once."

She takes her own face between his hands and leans in. Their lips are so close together that when she whispers, "This is so weird," the words are hot on his borrowed skin.

 

 

Whatever else he feels about the kiss, but he'd be lying if he didn't admit to a pang of disappointment when she pulls away and they're both still in the wrong body.

"Well, hell's bells," she says, his face falling with disappointment.

"Maybe," he stops to lick her lips, "uh, maybe we should try it again. To prove or disprove a hypothesis—"

"Works for me."

 

 

It's definitely not the outcome either of them expected. Not that anyone's complaining.

 

 

For the first time, for as far back as he can remember, when Sheldon wakes, there is no panic. There is no terror, no brief pause between asleep and awake that that threatens to freeze his blood in his veins.

Instead, there is soft, and warm, and heavy. There is a lassitude softening the muscles of the body draped against his side. His body, not to put to fine a point on it. A night of sleep hasn't been enough to reverse whatever it is that brought them here. To this bed, to these bodies, to this maze from which he can't find a way out.

Penny stirs against his shoulder, scratching the blunt nails of her borrowed hand through a patchy overnight growth of beard. Yawning so violently that it threatens to crack the jaw that until recently was his.

She cracks an eye open. Regards him blearily. "No dice?"

He doesn't say anything but Penny reads his response in the minute fluttering of the muscles around her own mouth and eyes.

She smiles, adding a wicked curve to his lips that he knows he's never managed on his own.


End file.
